In communications network devices, most terminal devices are powered by batteries, for example, lithium batteries or nickel batteries. Because either battery replacement or battery charging inevitably affects use of a terminal device, a key technical problem of the network device is how to make better use of an electric quantity of a battery of a network terminal device and prolong a usage time of the battery. Research has found that the lithium battery and the nickel battery have characteristics such as a non-linear discharge effect and a recovery effect. The non-linear discharge characteristic means that an electric quantity of a battery does not linearly decrease as use of a current, but exponentially decreases according to factors such as a current change, a service model, and a usage time. If discharge duration of the battery increases, more severe non-linear discharge occurs, and the electric quantity of the battery decreases at a higher speed. The recovery effect characteristic means that a part of an electric quantity of a battery is recovered if the battery is not used for a period of time after discharging. The non-linear discharge effect and the battery recovery effect differ for different types of batteries and different electric quantity statuses of batteries.
In the prior art, network data transmission is usually continuous. Using a Long Term Evolution (LTE) network as an example, after a synchronous channel is set up, a terminal continuously sends or receives data on uplink and downlink data channels. Therefore, a battery is kept in a discharge state during the network data transmission. Consequently, an electric quantity is consumed at a higher speed due to the non-linear discharge characteristic, and the battery recovery effect cannot take effect, thereby reducing an endurance time of the electric quantity of the battery.